Field of Invention
The invention relates to an optical lens.
Background of the Invention
In general, a long projection distance is required if a projector needs to project an image onto a large screen. Contrarily, a special wide-angle lens is required to shorten the distance from the screen to the projector if the image is to be projected onto the large screen from a short projection distance. That is, the wide-angle lens may effectively reduce the distance from the screen to the projector and project a relatively large image. However, the aberration issue derived from the wide-angle lens is one of the obstacles faced by designers.
In view of the above, how to design a lens with low manufacturing costs and favorable imaging quality has become one of the research topics to people having ordinary skill in the pertinent field.